Question 18

1. A car magazine makes the claim, "On average, there is no difference in gas mileage between automatic and manual transmission cars."
2. The gas mileage in miles per gallon (mpg) for30 different cars was recorded for both types of transmissions. A summary of the data is given below.
3. d=xautomatic-xmanual -d=0.87 sd=2.92 n=30
4. Using this summary data, test the car magazine's claim using a significance level of 0.05.

Select the best choice

At a significance level of 0.05, there is enough evidence to support the car magazine's claim that, on average, there is no difference in gas mileage between automatic and manual transmission cars.

At a significance level of 0.05, there is not enough evidence to reject the car magazine's claim that, on average, there is no difference in gas mileage between automatic and manual transmission cars.

At a significance level of 0.05, there is not enough evidence to support the car magazine's claim that, on average, there is no difference in gas mileage between automatic and manual transmission cars.

At a significance level of 0.05, there is enough evidence to reject the car magazine's claim that, on average, there is no difference in gas mileage between automatic and manual transmission cars.